(CNSNews.com) - The thought that John Bolton might be confirmed as the U.S. ambassador to the United Nations brought one Republican senator to the brink of tears on Wednesday.

Sen. George Voinovich (R-Ohio) choked up on the Senate floor, as he urged his colleagues to vote against Bolton's nomination on Thursday:

''I'm afraid that when we go to the [Senate] well, that too many of my colleagues -- (voice breaking) -- that too many of my colleagues are not going to understand that this appointment is very, very important to our country," Voinovich said.

"At a strategic time, when we need friends all over the world, we need somebody up there that's going to be able to get the job done.

"I know some of my friends say, 'Let it go, George, it's going to work out.' I don't want to take the risk," Voinovich said. "I came back here [to the Senate] and ran for a second term because I'm worried about my kids and my grandchildren. And I just hope my colleagues will take the time (pause) and before they get to this well, do some serious thinking about whether or not we should send John Bolton to the United Nations. I yield the floor."

Voinovich's emotional moment came one day after he sent a letter to his fellow senators, telling them, "In these dangerous times, we cannot afford to put at risk our nation's ability to successfully wage and win the war on terror with a controversial and ineffective ambassador to the United Nations."

Voinovich did not attend Bolton's confirmation hearings; and he surprised Republicans by raising last-minute objections to Bolton on April 19, just as the Senate Foreign Relations Committee was preparing to vote on Bolton's nomination.

Voinovich's objections prompted one group to run radio ads against him in Ohio, and it put him under intense pressure from Republicans in Congress and at the White House.

Because of Voinovich's objections, the committee postponed a vote on Bolton for several weeks. The nomination finally went to the full Senate on May 12 - but without a committee recommendation.

On May 12, before the committee vote, Voinovich said he would vote to send Bolton's nomination to the full Senate Voinovich because "we owe it to the president to give Mr. Bolton an up-or-down vote on the floor."

But Voinovich said he would vote against Bolton on the Senate floor. "I really don't believe he's the best man we can send to the United Nations," he said.

Voinovich said he'd met with Bolton and liked him. He called Bolton a "decent man" and described their conversations as "candid and cordial."

Most of Voinovich's Republican colleagues say Bolton, with his blunt, no-nonsense attitude, is the right man to represent U.S. interests at the United Nations, and he's expected to be confirmed.